http://www.cnn.com/2007/TECH/space/01/1 ... index.html
According to a spokesman for the National Security Council, the ground-based, medium-range ballistic missile knocked an old Chinese weather satellite from its orbit about 537 miles above Earth. The missile carried a "kill vehicle" and destroyed the satellite by ramming it.
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Low Earth-orbit satellites have become indispensable for U.S. military communications, GPS navigation for smart bombs and troops, and for real-time surveillance. The Chinese test highlights the satellites' vulnerability.
"If we, for instance, got into a conflict over Taiwan, one of the first things they'd probably do would be to shoot down all of our lower Earth-orbit spy satellites, putting out our eyes," said John Pike of globalsecurity.org, a Web site that compiles information on worldwide security issues.
"The thing that is surprising and disturbing is that [the Chinese] have chosen this moment to demonstrate a military capability that can only be aimed at the United States," he said.